X-Band Directional Coupler
Directional Couplers and the X-band frequency: The Basics
RF couplers are passive components that are utilized to test out entering high frequency signals. There are a few types of these RF couplers, one of which is the directional coupler. This is a four-port component that has an input and an output port. One of which is designated for the coupled signals and another port can be terminated internally at any time. The basic purpose of this tool is utilized in RF and microwave signal routing for isolating, separating or fusing together of signals. One can see directional couplers work in a wide array of measurement applications, such as:
- Monitoring of Power
- Leveling of Sources
- Signal Sources Isolation
- Swept Transmission and Reflection Measurements
Directional couplers that use frequency bands are also available for use. They help further improve the function of the directional couplers in testing out the frequency signals before pairing occurs, one example would be the X-band directional coupler. This frequency band is commonly used in military and government institutions that monitors the weather, controls the air traffic, tracking of defenses and detecting speed in vehicles for enforcing the law.
In addition, the X-band frequency produces short wavelengths. Short wavelengths in military radar systems allow for higher resolution imagery for target identification. Also, this frequency band has a high resistance in the rain. So, frequency signals can still travel despite the heavy rains.
The Basics of Directional Couplers
Generally, the main line in the directional coupler is the one between port 1 (The Input Port) and port 2 (The Output Port) and are suited to carry high power levels. The other parts in the directional coupler circuitry are regularly more suited for carrying lower powers as their main purpose is to carry a tiny part of the main line power.
Ports 3 (The Forward Coupled Port) and 4 (The Reverse Coupled Port) may possibly possess smaller connectors to easily identify them from the main line ports of the directional coupler. Sometimes, the secluded port is terminated with either an internal or external matched load that would usually reach up to 50 ohms.
While the particular ports are provided with labels on the component, this is usually more of a physical challenge as some ports will be made to carry high powers than others. As a matter of fact, a port can be classified as the input, and this will usually end up in the directly connected port being the transmitted port, the adjacent port now being the coupled port and the diagonal port now functioning as the isolated port.
A Quick Rundown on the X-band Characteristics in Satellite Communications
The X-band when used in satellite communications for military uses offers features that are designed to meet the needs the military and counters threats in the systems. Those features include:
- Steerable Beams
- High Power Spectral Density
- Nuclear Events and Abnormal Space Weather Resistance
- Laser Threat Protection
The X-band directional coupler, as what has been detailed above, serves to pair incoming high frequencies in the two ports (ports 1 and 2) and examines them before being coupled while the X-band helps with the process by continuing transmissions even in heavy rains.